I thought this would be an easy one. Not so. What works in Drupal 6 doesn't necessarrily work in Drupal 7. Let's take a simple example. How about a script that allows you to show/hide one or more paragraphs. I did a quick Google search and found numerous examples.
This may well qualify as a Drupal cheap trick. But it is pretty darn useful if you ask me. The use case - I have a custom content type for daycares. In it, daycare owners can advertize the number of available spaces they have at any time. Creating a list of daycares showing available spaces is, of course, easy with Views. But what if I would like to show the total number of available spaces for the listed daycares. How would I do that? At first, it's not obvious. But after the usual searching spree, I found the perfect solution.